Sweeping machine

ABSTRACT

A sweeping machine with dust withdrawal for floors and carpets with at least one motor-driven rotatable cleaning tool partially protruding downwardly from the machine housing, in which the cleaning tool is driven by the motor through the intervention of a transmission, the axes of rotation of said motor and of said transmission being substantially parallel to each other and to the plane to be swept by said tool said tool being supported by arm means pivotable either about the axis of rotation of said motor or about the axis of rotation of said transmission means. That end of the arm means remote from the tool is provided with or forms a spiral spring for continuously urging the arm means and thereby the tool against the floor.

0 1 1; United States atent 1 [111 3,772,727

Wiirwag 1 Nov. 2%, 1973 SWEEPING MACHINE 3,448,485 6/1969 Worwag 15 372x Inventor: Eberhard Wfirwag, Stuttgart, FOREIGN PATENTS 0R APPLICATIONSGermany 995,550 6/1965 Great Britain 15/366 [73] Assignee:Progress-Elektrogerate Mauz &

StuttgarFBomany, Primary Examiner-John Petrakes Germany AssistantExaminer-C. K. Moore Filed: p 5, 1971 Attorney-Walter Becker 21 A 1.No.: 134 81 1 PP 3 57 ABSTCT [30] Foreign Appumtion Priority Data Asweeping machine with dust withdrawal for floors A l 8 1970 G p 20 18667 8 and carpets with at least one motor-dnven rotatable emany cleaningtool partially protruding downwardly from the machine housing, in whichthe cleaning tool is [52] US. Cl. 15/49 C, 15/333, 1154737922, driven bythe motor through the intervention of a Int m 11/32 transmission, theaxes of rotation of said motor and of Said transmission beingSubstantially parallel to each [58] Field of Search 15/41 R, 49 C, 50 C,

other and to the plane to be swept by said tool said 15/79, 98, 355,356, 368, 371, 372, 389, 383

tool being supported by arm means plvotable either R i Used about theaxis of rotation of said motor or about the l e emmes n axis of rotationof said transmission means. That end UNITED STATES PATENTS of the armmeans remote from the tool is provided 2,079,293 5/1937 Kirby 15/389 Xwith or forms a spiral spring for continuously urging 2,179,963 11/1939SPadOIIB-H 15/49 CX the arm means and thereby the tool against thefloor. 3,012,267 12/1961 Kemnitz 15/372 2,197,641 4/1940 Holm-Hansen15/389 X 7 Claims, 3 Drawing Figures PATENIEDnuv 20 I975 SHEET 1 CF 2 Inventor. ,4 CQv- 443.

PAIENIEUnuveo 197s SHEET 2 OF 2 //7 ventor: fzayazw 4 3.

, SWEEPING MACHINE The present invention'relates to a sweeping machinewith dust withdrawal for carpets and the like with at least onemotor-driven cleaning tool, such as a brush roller or the like, which isrotatable about an axis parallel to the sweeping plane, the cleaningtool partially protruding from the housing of the machine and beingjournalled so as to be pivotable about a shaft arranged in the housingand parallel to the tool while being under a load so as to be urgedtoward the sweeping plane.

It has been suggested to provide the motor housing with at least onesupporting arm at the end of which there is journalled a brush roller.The motor together with the supporting arms for the brush roller andwith the brush roller itself forms a structural unit which as a unit canbe pivoted about an axle in the housing. The brush roller which has anaxis parallel to the sweeping plane partially protrudes from the housingof the sweeping machine or sweeper and is under a load so as to be urgedtoward the sweeping plane.

It has furthermore been suggested to provide the height adjustment ofthe brush roller with an arrestable lifting device in order to be ableto use the sweeper also as a pure vacuum cleaner. In such an instancethe brush roller is by means of a lifting device pivoted upwardly awayfrom the sweeping plane so that the brush roller can no longer act uponthe carpet or the like, and only the blower system can be effective withregard to dust withdrawal.

Sweeping machines of the just mentioned type have I the drawback thatthey can be employed either only as pure sweeping machines or only aspure vacuum cleaners. The working height of the brush roller is notadjustable in conformity with the respective type of floor, i. e.,whether a carpet, rug or wood floor is involved.

It is, therefore, an object of the present invention so to design-asweeping machine of the above mentioned general type that the cleaningtool, for instance a brush roller, can be adjusted to the best possibleeffective height with regard to the respective floor cover or floormaterial to be worked, and that such adjustment is effectedautomatically.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompanying drawings, in which:

FIG. 1 is a diagrammatic longitudinal section through the sweepingmachine according to the invention in which the supporting armssupporting the cleaning tool are pivotable about the central axis of thedriving mo- FIG. 2 is a longitudinal section through a modified sweepingmachine according to the invention in which the armssupporting thecleaning tool are pivotable about the central axis of the intermediatedrive.

FIG. 3 is a fragmentary perspective and exploded view of parts of thepresent invention usable in sweep- I ing machines of FIGS. 1 and 2.

The problem outlined above has been solved by a sweeping machineaccording to the present invention which is characterized primarily inthat the pivot axis of the supporting arms for holding and journallingthe cleaning tool is coaxial with regard to the shaft of the motorand/or the output shaft of the intermediate gear or transmission. Thismounting of the two supporting arms about the central axis of the motorshaft or the output shaft of thetransmission permits the adjustment ofthe load of the cleaning tool with regard to the sweeping plane wherebythe most favorable cleaning effect will be realized with the leaststress exerted upon the floor surface to be cleaned.

The above mounting of the two supporting arms has the further advantagethat the belt required for driving the cleaning tool will during thelifting and lowering movement of the cleaning tool always remain undertension because the axial distance will with this movement of thecleaning tool not be subjected to any change. As a result thereof,always auniform transmission of the speed and torque from the motor tothe cleaning tool will be assured so that the heretofore necessaryaccessories, for instance, tensioning rollers for the belt, for adaptingthe length of the belt to a varying axial distance, are no longernecessary. Consequently, the present invention brings about aconsiderable technical simplification and a considerable extension ofthe life of the driving belt.

According to a further feature of the invention, one end each of the twosupporting arms may be journalled in a supporting member which may bearranged in axial alignment with regard to the shaft of the drivingmotor and/or in axial alignment with regard to the output shaft of thetransmission. In view of these features, with a lifting or loweringmovement of the cleaning tool, the spacing between the axis of thecleaning tool and the pivot axis will always remain the same so that abetter stability will be assured.

According to a further development of the invention, it is suggestedthat at least one end of each supporting arm is designed as a spiralspring. In this connection in particular the ends of the supporting armswithin the region of their axis of rotation are to be considered,whereas the other free legs of the spiral springs are designed assupporting and locating means for one bearing area of the cleaning tool.The employment of spiral springs of this type also results in a betterautomatic adaptation of the working height of the cleaning tool to therespective floor material to be cleaned.

The spiral end of a supporting arm is expediently journalled in asupporting part. The journalling may be provided within the supportingpart about the central axis of the motor shaft. According to anotherpossibility, the spiral end may be journalled within the supporting partabout the output shaft of the transmission.

According to a still further development of the last mentioned design,the tension of the spring of the spiral end of the supporting arm may bevaried by turning the element which receives the spiral-shaped end inthe supporting part. The coiled inner end of the spiralshaped supportingarm is with this construction held in an element the axis of rotation ofwhich is in axial alignment with regard to the central axis of thedriving motor or the output shaft of the transmission. By turning thesaid element which receives the spiral-shaped end of the supportingarms, the supporting arms acting as spiral spring are loaded more orless depending on the turning of the spring mounting in clockwise orcounterclockwise direction.

In this way the pressure exerted by the cleaning tool upon the surfaceareas to be worked can be varied. The spring tension or load of thespiral-shaped end of the supporting arms may, however, also in similarmanner be varied by turning the spring mounting. In this connection itis expedient to make the mounting arrestable in its respective positionby a corresponding locking element. In a similar manner this alsoapplies to the arrestability of the respective adjustment of the spiralspring mounting.

. According to a further feature of the invention it is advantageous tomake the supporting part or spring mounting adjustable in a steplessmanner or in steps.

Finally, it is suggested to provide the supporting member or springmounting with a scale to indicate the respective adjustment.

Referring now to the drawings in detail, the arrangement shown thereincomprises a housing 1 which is composed of the upper housing section laand the lower housing section 1b. The dust collecting container 2 isconnected to the rear end of the upper housing section la. The dustcontaining air which is drawn into the dust collecting container 2 bythe blower of motor 3 is filtered when it arrives from the cleaning toolchamber 4. The dirt is separated by the cleaning tool 5 from the floorsurface to be cleaned. The cleaning tool 5 partially protrudes from thelower housing section lb within the region of the skids 6.

The front portion of the housing rests upon the skids 6 whereas the rearportion of the housing rests upon the supporting rollers 7. The blowerof motor 3 is mounted between the bearing elements 8 one of which isshown in the drawings. The drive of the cleaning tool 5 is effectedthrough a belt drive 9, 11 through the intervention of a transmission 12for reducing the speed of the motor.

The cleaning tool 5 is mounted between the supporting arms of whichoneonly is shown in the drawings. The supporting arms 10 have their freelegs 10a connected to the bearing element 13. The other ends 10b of thesupporting arms 10 are spiral-shaped and are mounted in a receiving part14. These spiral-shaped ends 10b are wound around the receiving part 14in the form of a loose spiral so that the oscillating movement of thesupporting arms 10 is resiliently supported by this winding spiral whileby turning the receiving part 14 about the motor axis, the tension ofthe spiral springs may be increased or reduced. As a result thereof, thefree ends 10a of the supporting arms 10 are together with the cleaningtool 5 mounted thereon pressed to a more or less extent against thefloor surface to be cleanedl According to FIG. I, the spiral-shaped ends1012 of the supporting arms 10 are journalled about the central axis ofthe shaft of the motor 3 within the receiving part 14, whereas accordingto FIG. 2 the spiral-shaped ends 10b of the supporting arms 10 aremounted about the output shaft of the transmission 12 within thereceiving part 14.

In order to fix the once selected pressure of the cleaning tool 5against the surface to be cleaned, the receiving part 14 is providedwith a locking device and with a scale to indicate the adjustment.

The structure shown in FIG. 3 can be adapted to be used ineither of thespecific embodiments respectively illustrated in FIGS. 1 and 2.

FIG. 3 illustrates more specifically means for grippingthe end portionsof the springs, how receiving parts, indicated ,by numeral 14 in FIGS. 1and 2 are mounted to support the spiral ends, and such features as thescale means, locking device, and arresting means.

FIG. 3 shows in exploded view how receiving part 14 is rotatably mountedupon the shaft of the bracket or bearing element 8. The spiral endportion 10b of supporting arm 10 is, at 10c, inserted into and securedin groove 15 of receiving part 14 by tightening set screw 16 arranged inthe bore 14a. A retaining ring 17 is placed in the groove 17a on the endof the shaft 8a to secure thereon receiving part 14. Tensioning or levermeans 18 are fastened to receiving part 14, in the bore 14b thereof.With this tensioning or lever means 18, the receiving part 14, andthereby the spiral end 10b secured therein, may be turned clockwise orcounterclockwise to thereby respectively load more or less the spiralend 10b.

To change the load or spring tension of the spiral end 10b, a lockingdevice consisting of lever means 18 and notched groove 19 is used.Tensioning or lever means 18 is moved out of its respective notch 19aand into the groove 19 in the upper housing section 1a. The tensioningor lever means 18 is then moved in groove 19 in either direction intothe desired notch 19a to obtain the required spring load. The movementfrom groove 19 into the pertaining notch 19a occurs and the positionobtained is indicated by the markings A, B, C, D on the scale 20adjacent the notches 19a.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular showing in the drawings but alsocomprises any modifications within the scope of the appended claims.

What I claim is:

l. A cleaning machine for cleaning floors and carpets, which includes:housing means having an opening in the front portion of the bottom ofthe housing means, a cleaning tool rotatably supported within saidhousing means and adapted partially to protrude through said openingmotor means within said housing means for driving said cleaning tool,transmission means interposed between said motor means and said cleaningtool, the axis of rotation of said motor means and the axis of rotationof said transmission means being substantially parallel to each otherand to the plane adapted to be swept by said cleaning tool, and armmeans having one portion thereof supporting said cleaning tool andhaving the other end portion thereof spirally shaped and arranged aroundone of said axes of rotation with the free end of said spirally shapedend portion stationarily anchored; said spirally shaped end portionbeing tensioned so that said cleaning tool is urged against the surfaceto be cleaned below said opening.

2. A cleaning machine which includes: housing means having an opening inthe front portion of the bottom of the housing means, a cleaning toolrotatably supported within said housing means and adapted partially toprotrude through said opening, motor means within said housing means fordriving said cleaning tool, transmission means interposed between saidmotor means and said cleaning tool, the axis of rotation of said motormeans and the axis of rotation of said transmission means beingsubstantially parallel to each other and to the plane adapted to beswept by said cleaning tool, and arm means having one portion thereofsupporting said cleaning tool and having the other end portion thereofspirally shaped and arranged around one of said axes of rotation withthe free end of said spirally shaped end portion stationarily anchored,said spirally shaped end portion of said arm means continuously urgingsaid cleaning tool in the direction of the surface to be swept.

3. A cleaning machine according to claim 5 which includes normallystationary supporting means substantially coaxial with said axis ofrotation around which one end portion of said arm means is arranged, foranchoring the free end of said apirally shaped end portion of said armmeans.

4. A cleaning machine according to claim 3, in which said normallystationary supporting means are rotatable for adjusting the springtension of said spirally shaped end portion of said arm means.

5. A cleaning machine according to claim 4, which sion of said spiralshaped end portion.

1. A cleaning machine for cleaning floors and carpets, which includes:housing means having an opening in the front portion of the bottom ofthe housing means, a cleaning tool rotatably supported within saidhousing means and adapted partially to protrude through said openingmotor means within said housing means for driving said cleaning tool,transmission means interposed between said motor means and said cleaningtool, the axis of rotation of said motor means and the axis of rotationof said transmission means being substantially parallel to each otherand to the plane adapted to be swept by said cleaning tool, and armmeans having one portion thereof supporting said cleaning tool andhaving the other end portion thereof spirally shaped and arranged aroundone of said axes of rotation with the free end of said spirally shapedend portion stationarily anchored; said spirally shaped end portionbeing tensioned so that said cleaning tool is urged against the surfaceto be cleaned below said opening.
 2. A cleaning machine which includes:housing means having an opening in the front portion of the bottom ofthe housing means, a cleaning tool rotatably supported within saidhousing means and adapted partially to protrude through said opening,motor means within said housing means for driving said cleaning tool,transmission means interposed between said motor means and said cleaningtool, the axis of rotation of said motor means and the axis of rotationof said transmission means being substantially parallel to each otherand to the plane adapted to be swept by said cleaning tool, and armmeans having one portion thereof supporting said cleaning tool andhaving the other end portion thereof spirally shaped and arranged aroundone of said axes of rotation with the free end of said spirally shapedend portion stationarily anchored, said spirally shaped end portion ofsaid arm means continuously urging said cleaning tool in the directionof the surface to be swept.
 3. A cleaning machine according to claim 5which includes normally stationary supporting means substantiallycoaxial with said axis of rotation around which one end portion of saidarm means is arranged, for anchoring the free end of said apirallyshaped end portion of said arm means.
 4. A cleaning machine according toclaim 3, in which said normally stationary supporting means arerotatable for adjusting the spring tension of said spirally shaped endportion of said arm means.
 5. A cleaning machine according to claim 4,which includes a locking device associated with said spirally shaped endportion of said arm means for maintaining the respective adjusted springtension.
 6. A cleaning machine according to claim 3, in which saidsuPporting means are adjustable for adjusting the spring tension of saidspiral-shaped end portion of said arm means.
 7. A cleaning machineaccording to claim 1 which includes scale means associated with saidspiral shaped end portion of said arm means to indicate spring tensionof said spiral shaped end portion.